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381.
目前我国的环境标准制度存在诸多不足.环境标准本身科学性不强,存在着标准滞后、空白、总量控制标准少、确定和修改依据不明、缺少专门针对公众健康设定的指标以及针对同一环境要素数值交叉等问题,这同时也与环境标准的法律性质不明确、编制机构不中立、编制程序不完善、公众参与不足密切相关.而环境标准体系本身的不完善也带来环境标准适用上的困难和障碍.对此,需要从法律制度和政策选择上寻求突破,明确环境标准的法律地位和效力,建立环境标准制定和修改的规则,确立环境标准的适用原则和条件,从而进一步完善环境标准制度. 相似文献
382.
An improved method, a palladium-catalyzed cross-coupling reaction the so-called Suzuki-coupling, was used to synthesize 19 monofluorinated analogues (F-PCBs) of polychlorinated biphenyls (PCBs), including analogues of PCBs 28, 52 and 81. The coupling of chlorinated and/or fluorinated isomers of aryl boronic acids with bromo- and/or iodobenzenes gave the desired F-PCB congeners in good to excellent yields. The self-coupling product of the aryl boronic acids was the major impurity, but this limitation could be minimized. The influence of ortho-substitution by chlorine on the reaction time was studied in detail. The F-PCBs were characterized by means of 1H and 19F NMR and mass spectrometry (MS). F-PCBs show remarkably similar characteristics in many aspects to those of the corresponding non-fluorinated parent PCBs. Since fluorine is generally resistant to degradation, once incorporated into a substrate it functions as an indelible label that can be used to monitor structures and dynamics. F-PCBs may prove their usefulness as markers and tracers in mechanistic and toxicological studies. The aim of further research will be to test the suitability of fluorine as a sensitive probe in a broad range of applications, including synthesis, analytical, mechanistic and toxicological studies. 相似文献
383.
Research has found that human-caused noise can detract from the quality of the visitor experience in national parks and related
areas. Moreover, impacts to the visitor experience can be managed by formulating indicators and standards of quality as suggested
in park and outdoor recreation management frameworks, such as Visitor Experience and Resource Protection (VERP), as developed
by the U.S. National Park Service. The research reported in this article supports the formulation of indicators and standards
of quality for human-caused noise at Muir Woods National Monument, California. Phase I identified potential indicators of
quality for the soundscape of Muir Woods. A visitor “listening exercise” was conducted, where respondents identified natural
and human-caused sounds heard in the park and rated the degree to which each sound was “pleasing” or “annoying.” Certain visitor-caused
sounds such as groups talking were heard by most respondents and were rated as annoying, suggesting that these sounds may
be a good indicator of quality. Loud groups were heard by few people but were rated as highly annoying, whereas wind and water
were heard by most visitors and were rated as highly pleasing. Phase II measured standards of quality for visitor-caused noise.
Visitors were presented with a series of 30-second audio clips representing increasing amounts of visitor-caused sound in
the park. Respondents were asked to rate the acceptability of each audio clip on a survey. Findings suggest a threshold at
which visitor-caused sound is judged to be unacceptable, and is therefore considered as noise. A parallel program of sound
monitoring in the park found that current levels of visitor-caused sound sometimes violate this threshold. Study findings
provide an empirical basis to help formulate noise-related indicators and standards of quality in parks and related areas. 相似文献
384.
385.
Zarca Díaz de la Espina Eduardo Benavides Velasco Carlos 《Environmental monitoring and assessment》2000,62(2):169-174
The eighties were notable for awareness of the need to prevent defects and for orientation towards the client to improve the competitiveness of industrial enterprises. This objective of zero defects has meant for many enterprises a management orientation to zero environmental impact. In this article we analyse the special situation of industrial enterprises in Andalusia (Spain) in the establishment of environmental management systems, proposing a matrix of strategies for their development based on the analysis of strengths, weaknesses, opportunities and threats. 相似文献
386.
环境一号卫星环境应用系统工程及其关键技术研究进展 总被引:3,自引:1,他引:2
简介长达11年的国家重点项目“环境一号卫星环境应用系统工程及其关键技术研究”的核心内容及其重要研究成果,对环境一号卫星系统需求分析、设计理论、研制发射和运行应用全过程进行了完整的研究与实践,为环境一号卫星系统的建设、应用和业务运行奠定了重要基础。 相似文献
387.
综述了我国不同介质中挥发性有机物(VOCs)的环境监测方法标准,介绍了样品采集和前处理、分析方法、质量保证与质量控制等技术内容,以及VOCs监测技术的研究进展。分析了国内VOCs监管控制的现状和重点需求,并在此基础上提出了健全VOCs环境标准体系、完善分类监管的优先控制物种清单、尽快实现VOCs监测工作的常态化、推广应用先进的VOCs监测技术等建议。 相似文献
388.
389.
Sandra Schwindenhammer 《Journal of Environmental Policy & Planning》2016,18(1):102-120
A key characteristic of global organic agriculture governance through standards is the coexistence of regulatory fragmentation and regional integration. To reduce barriers to organic trade, especially for market participants from developing countries, international and transnational entrepreneurs increasingly promote the setting of organic agriculture standards (OAS) in different world regions, for example, in East Africa, the Pacific, or Asia. Although scholars from different disciplines have done a lot of research on the role of standards in global governance, we still know little about why and how regional standard-setting processes evolve. Applying findings from regime analysis, entrepreneurship, and political authority, the article introduces the concept of authority pooling. It argues that legal, moral, and technical authority sources interact in a blurred functional division of labour between the public and the private sector in standard-setting. The article presents results from a within-case study of the development of the East African Organic Products Standard using the process-tracing method. It detects the underlying causal mechanism by which international and transnational entrepreneurs pooled different authority sources and, thus, significantly influenced political actors in East Africa to set the first regional OAS in the developing world. 相似文献
390.
Mahesh Tiwari Sanjay Kumar Sahu 《Journal of environmental science and health. Part. B》2016,51(9):616-621
In order to study the distribution and ecotoxicological concerns of persistent organic pollutants, grab sediment samples were collected from different locations across Thane creek, India. Analyses of samples were carried out using gas chromatography (GC)–electron capture detector and GC–mass spectrometry techniques. In organochlorine pesticides (OCPs), DDT (1,1,1,-trichloro-2,2-bis(p-chlorophenyl) ethane), DDE (1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene), DDD (1-chloro-4-(2,2-dichloro-1-(4-chlorophenyl)ethyl) benzene) and α, β, and γ conformer of hexachlorocyclohexane (HCH), and 9 polychlorinated biphenyls (PCBs) congeners were analyzed in surface sediment samples. Concentrations of these pollutants in grab sediment samples may indicate their current use and impact on marine ecosystem. Average concentrations of total DDT (including DDD and DDE), HCH, and Σ9PCBs were found to be 4.9, 12.5, and 2.9 µg kg?1(dry weight) respectively. High concentrations of OCPs and PCBs were found at discharge locations in creek compared to other locations. Location-wise distribution of OCPs and PCBs indicates their high concentrations at the waste water receiving point. Data were compared for ecotoxicological impacts based on the levels specified in the sediment quality standards of the US Environmental Protection Agency and the Canadian Council of Ministers of the Environment. γ-HCH was found to have maximum potential to induce ecotoxicological impacts. 相似文献